10 CSS Rules Every Web Designer Should Know

Through experience as web designers we memorise all kinds of code syntax, hacks and snippets. With CSS in particular there is a number of rules and declarations that can really help transform your website designs and open up new possibilities when compared to older techniques. This post rounds up 10 declarations and tips that every web designer should have available in their CSS arsenal.

@media

@media screen and (max-width: 960px) {
}

The @media rule not only allows you to specify styling for your web page when printed. These days media queries are more associated with the creation of responsive or adaptive website designs. Create a media query using properties such as min-width to adjust your design according to the user’s viewport size.

background-size

body {
background: url(image.jpg) no-repeat;
background-size: 100%;
}

A cool and extremely useful CSS3 property that has now gained thorough browser support is background-size. At one point making a background scale to the size of its parent required some right messing around, but now just one line of code is all you need. Use this snippet to achieve the ever-popular full screen background image effect.

@font-face

One CSS3 property that has really helped transform the web over recent years is @font-face. We previously had all kinds of limitations regarding font licensing which held back this property, but now there’s bucket loads of fonts to choose from and a range of services that build upon the basic @font-face code. Use @font-face manually with freely available fonts, or via third party services such as Google Webfonts or Typekit.

margin: 0 auto;

#container {
margin: 0 auto;
}

The clever margin: 0 auto; declaration is one of the first snippets you learn when getting to grips with CSS. It’s surprising that no specific declaration for centering a block element was ever added to the CSS spec, but instead we’ve all come to rely on the auto margin workaround. Add margin: 0 auto; to centre any block element within its parent.

overflow: hidden

.container {
overflow: hidden;
}

There’s all kinds of float clearing solutions and hacks out there, but one pure and simple way to clear your floats is to simply use the overflow: hidden; declaration on the container of your floated elements. It doesn’t add a load of garbage to your stylesheet and it gets the job done in 90% of scenarios.

.clearfix

For those float clearing situations where overflow: hidden; doesn’t work, the best alternative is the clearfix technique. Remember you don’t have to use the clearfix class name, your could target this code to any of your HTML elements individually.

color: rgba();

.btn {
color: rgba(0,0,0,0.5);
}

PNG images used to be required for creating any kind of transparency effects in web design, but thanks to another advance in CSS transparency can now be created with the help of the RGBa color mode. Using RGBa in place of a hex value allows you to select a colour using its red, green and blue channels as well as setting an alpha level, such as 0.5 for 50% opacity.

input[type=”text”]

input[type="text"] {
width: 200px;
}

The input[type="text"] selector and advanced selectors as a whole are great for taking your CSS skills from intermediate to expert. Attribute selectors in particular are extremely useful for styling elements without the need for additional classes. What about using attribute selectors to target the submit version of an input element or add an icon to external links?

transform: rotate(30deg);

.title {
transform: rotate(30deg);
}

If I’m honest I’ve yet to find a use for CSS transform properties in a real design project, but the ability to manipulate HTML elements without Javascript is so cool it makes these properties worth remembering! Combine transform properties with CSS transitions to create some fun animation effects.

a {outline: none;}

a {outline: none;}

Nothing can spoil a design more than seeing a huge dotted outline spanning across the whole page when you click a link element. The a {outline: none;} declaration will remove this, but for accessibility don’t forget to also add :focus states to your links. If you don’t mind seeing the dotted border but wish it didn’t span the whole screen, just add a {overflow: auto; } to your stylesheet instead.

Overflow specifies what happens when content overflows its containing box. Clear specifies which side of the element floats are not allowed on. If "clear: both;" is declared, then the floated elements will be forced to stretch out to accomodate their container. You might use clear: both on a footer div to get, say, a sidebar and a main section of a page, which are unequal in height because of their content, to stretch the same amount all the way to the footer. Take a look at http://www.quirksmode.org/css/clearing.html for more info. I wish I were better at explaining it. Sorry if I confused you more!

Not all but, yes there were a few which I really didn't know like the outline: none for anchor tags. I thought this worked only for removing those yellow and blue outlines from text inputs. Great share I must add.

I agree. My job has a high percentage of people that use IE because of government regulations and such. It would have been nice if they would have mentioned which rules don't work in IE because not everyone can afford to say "well, download firefox/chrome/safari/etc, it will work there"

CSS can be a bit daunting for one if one is just getting started. And the post has shared the most important CSS rules that helps to one and give the better understanding of how to use CSS. Great job you have done my friend…

I'm one of the older schooled web developers where to clear floated elements you just created a class called "clearboth" and then inserted an empty div using that class. For me this is what works 100% of the time. The "clearfix" method I haven't used very often mainly because I've found several places where it absolutely does not work. I can't explain why it doesn't work, just that it simply does not work for me at least half the time.

The project I'm currently working is using a predefined template that uses the clearfix method. I've had several elements (usually divs) that are floated for one reason or another. I first tried using the clearfix on them so that any following elements would line up correctly but at least 50% of the time absolutely nothing came of using clearfix. However as soon as I removed the clearfix class and then inserted a div with a normal clearboth class after the floated elements, everything lined up just fine.

So I don't currently see myself using the clearfix method anymore. I mean why use it if it doesn't work?

Waht a nice blog you have! Really enjoyed reading all your posts about web design. From my point of view, it's important to follow above mentioned CSS rules, as they help a lot to keep up with website usability!

Nice always good to remember basics.. no relation to this is article i just wanted to say your blog rock simple and clean but the best so far seriously .
I compare all the webdesign blogs and you always come out with something different than the others thats what make it so good . keep it up

Great post. A perfect info source. Thanks for taking the time to discuss this, I feel strongly about it and love learning more on this topic. I desired to be able to many thanks because of this outstanding examine!!

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